Alternate word orders allowed: Lú an helíyel swin kílu; An helíyel lú swin kílu. The sky may or may not actually be blue.
Ulsi umpikwa introduces a counterfactual conditional. Both clauses of counterfactual conditionals use the subjunctive mood.
Some alternate word orders allowed: Lú an myau swin swatel, An myau lú swin swatel. Not allowed: *An myau lú(n) swatel: when used in this sense, lú modifies a complete sentence, so the regular verb must be there. Definitely not allowed: *An myau lan saki (swa) swatel: lam saki does translate to "look", but it doesn't mean "look" in this sense, but rather that the cat is looking at something.
This expresses some uncertainty as to whether the cat really is black, or if it just looks that way for some reason. Because of this, the verb changes to the subjunctive (swin instead of swan).
Not *An myau swin swatel lú pwili: that would only be used to contrast with what someone else thinks, or what one thinks at a later time. Also not *An myau swan swatel maus pemim; that means something else (see next example).
...not sure how to translate the "to be their color" part, FIXME
TODO this sentence seems confusing